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The sandbar shark (Carcharhinus plumbeus) was the cornerstone species of western North Atlantic and Gulf of Mexico large coastal shark fisheries until 2008 when they were allocated to a research-only fishery. Despite decades of fishing on this species, important life history parameters, such as age and growth, have not been well known. Some validated age and growth information exists for sandbar shark, but more comprehensive life history information is needed. The complementary application of bomb radiocarbon and tag-recapture dating was used in this study to determine valid age-estimation criteria and longevity estimates for this species. These two methods indicated that current age interpretations based on counts of growth bands in vertebrae are accurate to 10 or 12 years. Beyond these years, we could not determine with certainty when such an underestimation of age begins; however, bomb radiocarbon and tag-recapture data indicated that large adult sharks were considerably older than the estimates derived from counts of growth bands. Three adult sandbar sharks were 20 to 26 years old based on bomb radiocarbon results and were a 5- to 11-year increase over the previous age estimates for these sharks. In support of these findings, the tag-recapture data provided results that were consistent with bomb radiocarbon dating and further supported a longevity that exceeds 30 years for this species., Cited By (since 1996):3,
Fish and Fisheries, CODEN: FSYBA

Clonal growth and symbiosis with photosynthetic zooxanthellae typify many genera of marine organisms, suggesting that these traits are usually conserved. However, some, such as Anthopleura, a genus of sea anemones, contain members lacking one or both of these traits. The evolutionary origins of these traits in 13 species of Anthopleura were inferred from a molecular phylogeny derived from 395 bp of the mitochondrial 16S rRNA gene and 410 bp of the mitochondrial cytochrome oxidase subunit III gene. Sequences from these genes were combined and analyzed by maximum-parsimony, maximum-likelihood, and neighbor-joining methods. Best trees from each method indicated a minimum of four changes in growth mode and that symbiosis with zooxanthellae has arisen independently in eastern and western Pacific species. Alternative trees in which species sharing growth modes or the symbiotic condition were constrained to be monophyletic were significantly worse than best trees. Although clade composition was mostly consistent with geographic sympatry, A. artemisia from California was included in the western Pacific clade. Likewise, A. midori from Japan was not placed in a clade containing only other Asian congeners. The history of Anthopleura includes repeated shifts between clonality and solitariness, repeated attainment of symbiosis with zooxanthellae, and intercontinental dispersal., Cited By (since 1996):31,
Invertebrates, CODEN: EVOLA

The ophiuroid communities on the continental slope off central California were examined using box cores and trawls. Box cores were taken between 550 and 3085 m at sites southwest of the Farallon Islands, and otter and beam trawls were used below 2300 m at three sites between the Farallon Islands and Point Sur. Eighteen ophiuroid species from six families were identified. Eighty percent of the individuals collected with box cores belonged to two species, Ophiura leptoctenia and Ophiacantha normani, which were dominant between 1000 and 2000 m. The largest ophiuroid faunal break occurred at around 2000 m and was associated with elevated dissolved oxygen levels, decreasing sediment grain size, and increasing sediment organic content. A comparison of box-core and trawl data from below 2300 m showed that box cores undersampled the ophiuroid community on the continental slope, missing almost 50% of the species collected by trawls within the same area, whereas trawls underestimated ophiuroid densities, reporting on average 243 times fewer ophiuroids per m2 than did box cores. There was a change in species relative abundance patterns between sampling locations. Ophiuroids exhibited patchy spatial distribution patterns on both a small scale of around 0.1 m2 and a large scale on the order of 100-1000 s of square meters. (C) 2000 Elsevier Science Ltd., Cited By (since 1996):14,
Invertebrates, CODEN: DSROE

The Pacific sand lance (Ammodytes personatus) is a small, elongate forage fish that spends much of its life buried in the seafloor. We determined that the Pacific sand lance can burrow in a wide variety of sediments from silt to gravel, but it prefers coarse sand (0.50-1.00 mm grain size). In the absence of coarse sand, the Pacific sand lance chooses larger grain sizes over smaller ones. These preferences are independent of light or the compaction of sediment, and therefore indicate that visual cues and ease of entry are not primary means of choosing burial substrate. Instead, we speculate that the Pacific sand lance is morphologically adapted for rapid mobility in coarse sand and that coarse sand has enough interstitial spaces to enable respiration during protracted immersion. As an obligate burrower in specific sediments, the Pacific sand lance is a good candidate for habitat-based management. Substrate maps of 3 fishing grounds in southeast Alaska where the Pacific sand lance is abundant and where habitat-based management is practiced were used to create potential habitat maps. Different geologic histories have resulted in variable amounts of preferred (sand-gravel), suitable (sand mixed with silt, cobble-boulder, or rock outcrop), and unsuitable (mud, pebble-boulder) habitat for this species among regions. [ABSTRACT FROM AUTHOR], Article

A new deep-water catshark, Bythaelurus bachi, is described based on 44 specimens caught on the southern Madagascar Ridge in the southwestern Indian Ocean. The new species is the only stout-bodied Bythaelurus with oral papillae in the region and is distinguished from all congeners by the plain beige to light gray-brown coloration, high diversity in dermal denticle morphology, and presence of composite oral papillae. Despite resemblance in body shape, Bythaelurus bachi n. sp. is distinguished from its closest congener, B. naylori Ebert & Clerkin, 2015, by the presence of numerous large, partially composite papillae on the tongue and roof of the mouth (vs. papillae lacking), plain light coloration (vs. medium to dark brown ground color, light fin edges and a distinctly dark dusky-colored snout), only slightly enlarged dermal denticles on the anterior upper caudal-fin margin (vs. dermal denticles distinctly enlarged), a higher diversity in dermal denticle morphology in general, and smaller maximum size and size at maturity. The distinction of both species is also supported by molecular results. The new species differs from all other congeners in the western Indian Ocean in the stout body shape of large specimens, coloration, larger size, as well as several morphometrics, including larger claspers, longer eyes and dorsal fins, and shorter pelvic—anal and pelvic—caudal spaces. The genus is reviewed, a key to its species given.

135 Plankton samples were collected in the northwest Pacific Ocean and analyzed for their cadmium content. Concentrations were generally low (2 to 5 micrograms of cadmium per gram, dry wt) in all samples, except for the plankton collected off Baja California, where high values (10 to 20 parts per million) were consistently found on 2 cruises., Cited By (since 1996):24,
Oceanography, CODEN: SCIEA